Vote Cone — UninterpolatedVote Cone TransitionsReflecting on “Vote Cones”Vote Cones in Vega-LiteElection 2020: How reliable are different results at different stages?Election 2020 Vote–Time Correlation CartogramElection 2020 Vote Count Speed CartogramElection Cone — Iowa Senate 2016Election Cones — President 2016Election Cones — Senate 2016What’s the connection between these two election bar charts?Election 2020 DataElection 2020 Vote Margin CartogramElection 2020 Cone with Colored ContoursCalculate the percentage of remaining vote needed to overcome given absolute margin
Election 2020 Cone with Labeled Contours
import { presidentByState, president } from "1342cadc9354cc67"
import { select } from "@jashkenas/inputs"
file = presidentByState.get(stateKey)
a = file.candidates.find(d => d.party_id === "republican")
b = file.candidates.find(d => d.party_id === "democrat")
stateName = file.state_name
timeseries = file.timeseries.map(d => ({
x:
d.vote_shares[a.candidate_key] /
(d.vote_shares[a.candidate_key] + d.vote_shares[b.candidate_key]) || 0.5,
y: d.eevp / 100,
t: new Date(d.timestamp)
}))
final = timeseries.slice(-1)[0].x
color1 = "#dd2c35"
color2 = "#0080c9"
counties = []
// how's this file different??
(await FileAttachment("summary.json").json()).races[0].timeseries
accumulate = arr => {
const result = [];
const _N = d3.sum(arr, ({ n }) => n);
let _a = 0;
let _n = 0;
arr.forEach(function({ a, n }) {
_a += a;
_n += n;
result.push({ x: _a / _n, y: _n / _N });
});
return result;
}
getBest = data =>
accumulate(data.slice().sort((a, b) => d3.descending(a.a / a.n, b.a / b.n)))
getWorst = data =>
accumulate(data.slice().sort((a, b) => d3.ascending(a.a / a.n, b.a / b.n)))
bestRun = getBest(counties)
worstRun = getWorst(counties)
line = d3
.line()
.x(d => x(d.x))
.y(d => y(d.y))
function halo(text) {
text
.select(function() {
return this.parentNode.insertBefore(this.cloneNode(true), this);
})
.attr("fill", "none")
.attr("stroke", "white")
.attr("stroke-width", 4)
.attr("stroke-linejoin", "round");
}
renderHypotheticals = g =>
g
.selectAll("g.hypothetical")
.data([bestRun, worstRun])
.join("g")
.attr("class", "hypothetical")
.each(function(d, i) {
const uid = DOM.uid("hypo");
const sel = d3.select(this);
const path = sel
.append("path")
.attr("id", uid.id)
.attr("stroke-dasharray", "3,3")
.attr("d", line(i ? d : d.slice().reverse()));
sel
.append("text")
.attr("x", d => path.node().getTotalLength() / 2)
.attr("dy", 15)
.attr("fill", "white")
.attr("stroke", "none")
.attr("text-anchor", "middle")
.append("textPath")
.attr("href", uid.href)
.text(`If ${(i ? b : a).last_name} counties reported first`);
})
timeTicks = [
d3.min(timeseries, d => d.t),
...d3.timeHour
.range(...d3.extent(timeseries, d => d.t))
.filter(d => timeScale(d) < .99)
]
timeScale = d3.scaleTime(timeseries.map(d => d.t), timeseries.map(d => d.y))
timeFormat = d3.timeFormat("%I:%M %p")
timeAxis = g =>
g
.selectAll("g")
.data(timeTicks)
.join("g")
.attr("transform", d => `translate(${width}, ${y(timeScale(d))})`)
.call(g =>
g
.append("line")
.attr("stroke", d => (timeScale(d) > 0.5 ? "white" : "#ccc"))
.attr("x2", -5)
)
.call(g =>
g
.append("text")
.attr("text-anchor", "end")
.attr("x", -7)
.attr("dy", "0.3em")
.attr("fill", d => (timeScale(d) > 0.5 ? "white" : "#ccc"))
.text(d => timeFormat(d))
)
pctAxis = g =>
g
.selectAll("g")
.data([.25, .5, .6, .7, .8, 0.9, 0.95, 0.99])
.join("g")
.attr("transform", d => `translate(0, ${y(d)})`)
.call(g =>
g
.append("line")
.attr("stroke", d => (d > 0.5 ? "white" : "#ccc"))
.attr("x2", 5)
)
.call(g =>
g
.append("text")
.attr("x", 7)
.attr("dy", "0.3em")
.attr("fill", d => (d > 0.5 ? "white" : "#ccc"))
.text(d => pct(d))
)
pct = d3.format(".0%")
// currentShare ∈ [0,1] fraction of votes so far cast for Party A
// votesCounted ∈ [0,1] fraction of total votes that have been counted
// shareNeeded ∈ [0,1] fraction of remaining votes needed for Party A to win
value = (currentShare, votesCounted) =>
votesCounted === 1
? currentShare > .5
? -Infinity
: currentShare < .5
? Infinity
: NaN
: (currentShare * votesCounted - 0.5) / (votesCounted - 1)
// solve for z: z = (x * y - t) / (y - 1)
// solve for y: y = (t - z) / (x - z) and x!=z and t!=x
// solve for x: x = (t + (y - 1) * z) / y and y!=0 and y!=1
// solve for t: t = x y - y z + z and y!=1
contour = z => x => (0.5 - z) / (x - z)
newContours = d3
.range(0.1, 1, 0.1)
.filter(z => z !== 0.5)
.map(z => ({
z,
data: [...d3.range(0, 1, 0.02), 1]
.map(x => ({ x, y: contour(z)(x) }))
.filter(({ x, y }) => y >= 0 && y <= 1)
}))
_color = d3.scaleSequential(
[0, 1],
d3.interpolateRgb.gamma(2.2)(color1, color2)
)
color = d =>
d >= 1
? `url(${window.location.href}#checkerboard2)`
: d < 0
? `url(${window.location.href}#checkerboard1)`
: "#eee"
defs = `
${makeCheckerboard("checkerboard1", color1, checkSize)}
${makeCheckerboard("checkerboard2", color2, checkSize)}
${makeCheckerboard("smallCheckerboard1", color1, 5)}
${makeCheckerboard("smallCheckerboard2", color2, 5)}
</pattern>
`
makeCheckerboard = (name, color, checkSize) => `
<pattern id="${name}" patternUnits="userSpaceOnUse" width="${checkSize *
2}" height="${checkSize * 2}">
<rect width="${checkSize * 2}" height="${checkSize *
2}" x="0" y="0" fill="#ddd" />
<rect width="${checkSize * 2}" height="${checkSize *
2}" x="0" y="0" fill="${color}" opacity="0.3"/>
<rect width="${checkSize}" height="${checkSize}" x="0" y="0" fill="${color}" opacity="${
checkSize < 10 ? 1 : 0.2
}" />
<rect width="${checkSize}" height="${checkSize}" x="${checkSize}" y="${checkSize}" fill="${color}" opacity="${
checkSize < 10 ? 1 : 0.2
}" />`
checkSize = 16
thresholds = [-Infinity, ...d3.range(0, 1, .1), 1]
grid = {
const q = 4; // The level of detail, e.g., sample every 4 pixels in x and y.
const x0 = x.range()[0] - q / 2,
x1 = x.range()[1] + q;
const y0 = y.range()[0] - q / 2,
y1 = y.range()[1] + q;
const n = Math.ceil((x1 - x0) / q);
const m = Math.ceil((y1 - y0) / q);
const grid = new Array(n * m);
for (let j = 0; j < m; ++j) {
for (let i = 0; i < n; ++i) {
grid[j * n + i] = value(x.invert(i * q + x0), y.invert(j * q + y0));
}
}
grid.x = -q;
grid.y = -q;
grid.k = q;
grid.n = n;
grid.m = m;
return grid;
}
// Converts from grid coordinates (indexes) to screen coordinates (pixels).
transform = ({type, value, coordinates}) => {
return {type, value, coordinates: coordinates.map(rings => {
return rings.map(points => {
return points.map(([x, y]) => ([
grid.x + grid.k * x,
grid.y + grid.k * y
]));
});
})};
}
contours = d3
.contours()
.size([grid.n, grid.m])
.thresholds(thresholds)(grid)
.map(transform)
x = d3.scaleLinear(zoomScale(yDomain0), [0, width])
y = d3.scaleLinear([yDomain0, 1], [0, height])
zoomScale = d3.interpolate([0, 1], [0.49, 0.51])
height = Math.floor((width + 28) / 4) * 4
d3 = require("d3@6")
md`---
## To-do
- Rip out unnecessary D3 contour code, since there’s a simple analytic solution, DUH!
- Respect the domains such that it’s easier to zoom in on one part
- Animate zooming in on the end of the funnel!!
- Account for fuzzy estimate of votes remaining!!
- Code-code line by which way it’s leaning?
- Leave room for some info on what’s remaining?
- Bring back the “same updates in a different order” counterfactual cone of paths, which may be very important this year as the plausibiity of shifts is challenged
- transition b/w time equal-interval and percentage equal-interval`
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
